Pulley.



H. J. GILBERT. PULLIBY. APPLICATION run) n 4, 1906.

' Patented May 7, 1912.

HENRY J'. GILBERT, 0F SAGINAW, MICHIGAN.

PULLEY.

Specification of Letters Patent.

Patented May 7, 1912.

Original application filed March 8, 1904, Serial No. 197,072. Dividedand this application filed May 4,

1906. Serial No. 315,165.

To all whom it may concern:

Be it known that I, HENRY J. GILBERT, a citizen of the United States,residing at Saginaw, county of Saginaw, and State of Michigan, haveinvented certain new and useful Improvements in Pulleys, of which thefollowing is a specification.

My invention pertains to pulleys and the like and more particularly topulleys made of sheet metal and the object thereof is to produce apulley of this character so constructed and arranged as to possess theelements of strength, rigidity and durability.

The various features of improvement and advantage of my pulleyconstruction will be apparent from the description hereinafter given.

In the accompanying drawing, Figure 1 is a side elevation of a pulleyembodying my improvements; Fig. 2 a sectional elevation of the hubportion of one of the pulley halves or sections, the section being takenlongitudinally of the spoke arm; Fig. 3 a perspective of thestrengthening piece or plate illustrated in Figs. 1 and 2 in associationwith the other parts of the pulley structure; and Fig. 4 a cross sectionof one of the spoke arms.

The same reference characters are used to indicate corresponding partsin the several views.

Referring to the present embodiment of my invention, the pulley is ofthe usual twopart or two-section construction, having the twosemi-circular rim segments A, A which abut at their meeting ends to formthe complete circular rim and also having the two parallel spoke arms B,B which are secured at their ends to the rim structure in any suitablemanner so far as my present invention is concerned. In addition to thespoke arms B, strengthening spoke arms C, C at right angles to the mainspoke arms may be employed, such arms C, C being connected at theirends, respectively, with the rim structure and with the hub portion ofthe main spoke arms.

The main spoke arms B, B are U-shaped in cross section, as indicated inFig. 4c and are provided at their middle with curved hub portionsforming a shaft bore or opening and two portions extending substantiallyradially therefrom to the point or place of attachment thereof to therim segments. The main spoke arms which are slightly separated from eachother, are clamped together and upon a shaft (either directly or throughthe medium of a buslr ing) by means of clamp-ing bolts D, D. In thepresent instance, I provide the shaft opening or bore with a hub thimbleE of the split type.

The purpose of my present invention is to provide novel and eflicicntmeans for strengthening the hub port-ion of the spoke arms and resistingthe crushing pressure which is incident to the clamping of the spokearms onto the shaft and tends to flatten the hub portion, especiallywhen the latter is extended longitudinally, that is in the direction ofthe axis of rotation. To this end, I provide the hub portion of each ofthe main spoke arms B, B with a strengthening plate F which is of theirregular shape illustrated in Fig. 3, each plate being interposed inthe annular space between its half of the thimble E and the shaft boreof its spoke arms which are concentric with each other. Thisstrengthening plate presents its edges, respectively, to the inner faceof the hub portion of the spoke arm and the outer face of the halfthimble, if a thimble is employed.

As herein shown, each strengthening plate has an arched central portionso as to be saddled upon its half thimble and also has rectangular endsf arranged to fit beneath the flattened surface of its spoke arm, and,by preference, to extend slightly beyond the line of the clamping bolts,all as clearly illustrated in Fig. 2. These strengthening plates aresecured to the spoke structure and preferably also to the half thimbles,in suitable manner, as for instance by means of the oppositely extendinglugs f located at the center of the strengthening plates and passingthrough holes in the spoke structure and bushing, respectively, suchpr0- jections or lugs being headed down in the manner of riveters. It isobvious from this description that these strengthening plateseffectually maintain the concentric relationship between the thimble andthe hub portion of the hub structure and thereby prevent a crushing inor flattening of such hub portion when the clamping bolts are tighteneol.

I claim:

1. In a pulley, the combination, with a rim, of a pair of spoke armsconnected therewith, the central portion of such spoke arms beingoutwardly curved to form the shaft bore or hub portion of the pulley,and strengthening plates each having a central portion curved tocorrespond with the shaft opening or hub portion of the pulley and endportions arranged to bear against the inner face of the spoke arms atpoints beyond the hub portions thereof; substantially as described.

2. In a pulley, the combination, with a rim, of a pair of spoke armsconnected therewith, the central portion of such spoke arms beingoutwardly curved to form the shaft bore or hub portion of the pulley,and strengthening plates each having a central curved portioncorresponding to the hub portion and having ends arranged to bearagainst the inner face of the spoke arms at points beyond the hubportions thereof, said central portion of each strengthening plate beingsecured to the hub portion of its spoke arm, substantially as described.

3. In a pulley, the combination of a rim, a hub thimble, a pair of spokearms having straight end portions and a central portion outwardly curvedso as to be substantially concentric with the hub thimble, and plates,each having a curved part arranged between said thimble and the curvedportion of the spoke arms and having end portions arranged beneath thestraight portions of the spoke arms; substantially as described.

4. In a pulley, the combination of a rim, :1 pair of spoke armsconnected therewith, the central portion of such spoke arms beingoutwardly curved to form the hub portion of the pulley, andstrengthening plates positioned transversely of the pulley axis andconsisting of plates placed on edge with their outer edges bearing uponthe inner faces of the hub portion, said hub portions having rivet holesand. said plates having projections f adapted to pass through said holesto form rivets; substantially as described.

5. In a pulley, the combination of a rim, a pair of spoke arms connectedtherewith, the central portion of such spoke arms being outwardly curvedto form the hub portion of the pulley, and strengthening platespositioned transversely of the pulley axis and consisting of platesplaced on edge with their outer edges bearing upon the inner faces ofthe hub portion, said plates having projections f on opposite edges, anda hub thimble which together with said hub portion have holes to receivesaid projections; substantially as described.

HENRY J. GILBERT.

Witnesses EDWARD REOTOR, LoUIs B. ERWIN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, .D. G.

